在Rifamycin抗生素生物合成期间异步链延长的分子基础
Chengli Liu1, Ryan C West1, Muyuan Chen2
1Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA 90089, USA.
bioRxiv : the preprint server for biology
|July 9, 2025
概括
这项研究揭示了 rifamycin合成酶 (RIFS) 酶复合物如何构建抗生素前体. 结构和动力学分析显示了蛋白质域如何相互作用,以指导聚基酸合成酶系统中的复杂化学反应.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 结构生物学 结构生物学
背景情况:
- 利法胺合成酶 (RIFS) 是一种巨大的酶复合体,对于利法胺B抗生素生产至关重要.
- RIFS作为混合酶组装线的功能,结合非核糖体合成酶和多基合成酶模块.
- 关于净化RIFS组件的详细结构和生物化学数据是有限的.
研究的目的:
- 通过分析其第一个聚基酸合成酶模块 (M1) 来阐明RIFS的生物合成机制.
- 调查在多基链延长过程中M1模块内的结构和动态相互作用.
- 了解蛋白质结构如何影响大合成酶系统中的酶活性.
主要方法:
- 醇选择性交叉链接来探测蛋白质与蛋白质之间的相互作用.
- 低温电子显微镜 (cryo-EM) 用于高分辨率的结构分析.
- 单旋转动力测试用于测量反应速率和中间体形成.
主要成果:
- 交叉链接数据揭示了合成酶 (KS) -基质载体蛋白 (CP) 相互作用中的结构不对称性.
- Cryo-EM揭示了M1模块的独特架构,支持域共迁移.
- 删除C端二维接口增加了KS-CP相互作用,但没有产品形成,这表明了调节作用.
结论:
- 细菌聚基合成酶中的C端二维接口可能会在KS活性位点之间协调CP域的移动.
- 了解这些分子细节对于设计新生物合成酶至关重要.
- 这项研究提供了对天然抗生素生物合成和人工大合成酶的设计的见解.
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